Collapsible form for building culverts.



G. A..BESSER. E FORM FOR BUILDING GULVBRTS.

952,869, Patented. Mar.22,191 0. V 2 SHEETS- SHEET 1.

GOLLAPSIBL APPLICATION FILED DEC. 4, 1908.

0. A. BESSER. GOLLAPSIBLB FORM FOR BUILDING GULVERTS.

APPLICATION IILED 1320.4, 1908. I

Patented Mar. 22, 1910. 2 SHEETS-SHEET 2.

Tamas r .EENT nn CHARLES A. B ESSEE, OF MOUNT PLEASANT, IOWA.

CJL'LAPSIBLE FORM FOR BUILDING CULVERTS.

ceases.

To all whom it may concern: 7

Be it known that I, CHARLES A. Bnssnn, a citizen of the United States, residing in Mount Pleasant, in the county of Henry and State of Iona, have invented a new and useful Improvement in Collapsible Forms for Bnildmg Culverts, of which the following is a specification.

This invention relates to a collapsible form or core designed more especially for use in constructing concrete or other culverts, sewers, drains and the like, the concrete being applied to the outside of the form in any approved manner, and the form removed after the concrete has sufiiciently set.

The invention has for one of its objects to provide a form which can be adjusted for constructing culverts of difierent sizes, so that one form will answer the purpose of a number of forms of the various types with which I am acquainted, this result being obtained by, the employment of a plurality of curved sheet metal plates so transverse section, s owing the form fully expanded and drawn on a further increased scale. Figmi is a detail view of one of the shape of the form is maintained throughout...

1 c m .the range of adjustment of'the form.- In

assembled and connected with operating means that the form will preserve its cylindrical shape throughout its range of adjustment from its maximum to its minimum diameter.

A further object of the invention is the employment of a novel arrangement of screw-actuated .collarsand links connected therewith and with the platesof the cylindrical form, whereby the plates are drawn inwardly or outwardly without having longitudinal movement, and, atthe saine time, the plates slide freely-one-over another while preserving the circular shape of the form.

With these 'objectsin view and others, as will appear as the description proceeds, the invention comprises the various novel features of construction and arrangement of arts which will be more fully described ereinafter and set forth with particularity in the. claims appended hereto. In the accom anying' drawings, which "illustrate one em odimentof the invention,

Figure 1 is a side viewofthe form fully expanded. Fig. :2 is a lon itudinal section drawn on an'enlar ed, sca l. Fig. 3 is a screw-actuated collars.

Fig1 5 is ajtran'sverse section of the form- "I Specification of Letters Patent.

Application filed. December 4, 1908. Serial No. 466,038.

latented Mar. 22, 1910.

and drawn on a larger scale than Fig. 3. Fig. 6 is a diagrammatic view, showing the various plates of the form in their normal shape by full lines, and by dotted lines when placed under tension, the plates being drawn substantially on the scale shown in Fig. 3.

V Similar reference characters are employed to designate corresponding parts throughout the views.

In the present instance, I have elected to illustrate the form of the six plate type, which has been found, in practice, satisfactory for constructin culverts varying from two to four feet in ciameter, but it is to be understood that the number of lates and theirsize can be changed according to the diameter of the culvert to be built.

Referring to the drawings, 5 designates 7 an operating shaft for contracting or expending the form, the same being composed of parts connectedtogether by a sleeve or other coupling 6, and each part has a right and left thread 7 and 8, respectively. En- 8 gaging these threads are collars 9 and 10, which are adapted to move toward or away from each other by the rotation of the shaft 5. The collar 9 is formed with outwardlyextendin slotted lugs 11 for receiving t e 3 inner en s of aset of links 12 that are pivotally connected with the lugs and have their outer ends connected with the parts'of the cylindrical form or shell. The collar 10 is also provided with outwardly-extending 9 peripheral slotted lugs 13 for receiving the inner ends of a second setof links 14. As shown in Fig. 4, the lugs are offset from a radial line, and, as shown in Fig. 3, the lugs of the collar 9 are sii htly staggered with re 9 spent to the lugs oft e collar 10, so that the set of links 12 can overlap or extend across corresponding links of the set 14. The outer ends of both sets of links are connected with internal longitudinally extending ribs 1 formed by tee or angle bars 15 secured to the variousparts of the cylindrical form. By

this arrangement, the turning of the shaft 5 causes the parts of the form to move inweirdly or outwardly by the collars 9 and l 10 traveling toward or aways-from each other and thereby actuating the two sets of links. f The cylinder or shell of the form is composed oi a. lurality of arcuate sheet metal lates so nested, together'that the circular 1 the present instance, the shell consists of a top plate 16, a pair ofopposed upperside plates 17, a pair of opposed lower side plates 18, and a bottom plate 19. The top and bottom plates 16 and 19 have their angle bars 15--fastened thereto in a median line,

while the angle bars of the side plates'are' connected to the upper edges of the latter. By this arrangement, both longitudinal edges of the top and bottom plates, and the lower edges of the side plates, are free to move inwardly and outwardly between the full and dotted line positions shown in Fig.

edges of the plates 18 overlap and bear on the outer face of the plate 19. It will thus be seen that the lap joints are so disposed that water cannot enter the formbnt is shed away from the joints. When the form is fully expanded, as shown in Fig. 3, the radial arms or links 12 and 14 connected with the plates 17 and 18, withstand the inward tension of the plates 16 and 17 while the in ward tension of the plates 18 opposed bv the outward tension of the plate 19.

' lVhen the form is contracted to its minimum diameter, its circumference is conr posed of the plates 16 and the two plates 17, the plates18 and 19 being nested withinthe cylinder, as shown in Fig. *The plates correspond in this figure to the full line position of the plates shown in Fig. 6, with the exception of the bottom plate 19, which is in its dotted line positioh. During the contraction of the cylinder, the plates 18 slide over the plate 19 and meet at the center of the latter, and the plates 17 slide over ,the plates 18 and come together opposite the meeting edges of the last-mentioned plates, while the plate 16 slides over and partially covers the plates 17.' W'hen the screw shaft is turned in theoppbsite direction to expand the cylinder, the plates slide in the reverse order to uncover the plates until the maximum diameter shown in Fig. 3, is reached. The shaftli, which. is manipulated by a hand wheel 17' at one end of the form, is disposed at ap roximately the about which the severa plates are struck as. acenter, and the links or arms 12 and 14 are arranged in pairs sixty degrees apart. and one pair for each plate. Each pair 0 links 12 and 14:, connected with the same reinforcing rib or bar 15, are pivoted at 'opposite sides of the inwardly or radially disposed flange or the rib, so that the two links can move across eachv other without contact. ,7

In practice, the form is set up in the position where the culvert is to be built and the screw shaft turned to produce the proper diameter for the form. .The concrete or other plastic material is then applied around the form and allowed to set for a sufiicient time, when the form is loosened and re 5 moved. Inorder to loosen the form, it .is merely necessary to turnthe screw in a di-' rection to draw the pldtes inwardly for re-- ducing the diameter to permit of theready 1 withdrawal of the form longitudinally. In 0 manipulating the screw, the plates of the form cannot move longitudinally by reason of the crossed relation of the links 12 and 14.

From the foregoing description, taken in connection with the accompanying draw- 35 ings, the advantages of the construction and of the method of operation will be readily apparent to those skilled in the art to which the invention appertains, an'd whileI have described the principle of-operation of the invention, together with the device which I now consider to be the best embodiment thereof, I desire to have itv understood that the device shown is merely illustrative, and that such changes may be made when desired as are within the scope of-the claims appended hereto. v

Having thus described the invention, what- I claim as new, and desire to seureby Letters Patent, is

1. A collapsible form including a plu- 1 rality of arcuate plates chan cable in curvature to vary the diameter 0 the form, one plate having a curvature approximating the maximum diameter of the form, and another plate approximatingthe minimum diameter thereof.

2. A cylindrical expansibl'e and contractihis form composed of a plurality of arcuate sections, one of the sections'having a normal curvature approximatingthe maximum diameter of the form and another section a normal curvature approximating the minimum diameter of theform.

3. A contractible and expansible cylindrical form composed of sheet metal curved plates arranged in overlapping relation and 'slidable one on another. certain of the plates having a curvature equal to the minimum diameter of the form and another plate having acurvature equal to the maximum d1- ameter of the form.

4. An expansible and contractible form composed of a plurality of curved resilient sections arrangedto slide one over'another, some of the sections tending at all times to assume a curvature approximating the'minimum diameter of the form, and mechanism for moving the sections inwardly or outwardly in a radial direction and simultaceases neously sliding the plates on each other to change the diameter of the form. I 5. A 'contra'ctible and expansible t'o'rm composed of a plurality of'sections slidable one over another and all contributing to constitut'e the form when the latter is fully ex- "panded and certain of the sections entirely covering other sections 'when the form is completely contracted, some of the sections I 'havinga normal curvature approximating v the minimum diameter of the form, with a mechanism connected with the several sections for expanding and contracting the form.

' (LIA contra ctible and expansible the form and another section having a curva ture equal to the maximum diameter of the form.

7. A hollow 'expansible and contractible form composed of flexible sheet metal sections disposed parallel and eachslidable on the adjacent sections and changeable in curvature during the sliding movement, and

radially-disposed links, some of which are 5 connected. with the middle portions of cer- 1 tain or the sections and the others connected adjacent one of'the longitudinal edges of :the remaining sections, and means for shifting the links toslide'the, sections on each 40 other for contracting and expanding the form. 1 :8. A hollow contractible and expansible form consistingof aplurality of arcnate plates overlapping and slidableone on another, Links cormeetedwith the middle por- ',tions of two diametricallyglisposed plates, =linkS connected with one edge of each of the remaining plates, and Emeansf for: actuating a the li'nlis7for contracting and "expanding the f;0gm,-i1ll the plates 'except one of the-saiddiametrically-disposed plates-having a normal curvature approximating the minimum diameter of the form .and the other plate ghaving a normal curvature approximating -lthe maximum diameter of theforni.

" t); A form ofthe character described comprising a top plate, 'u per side plates having their upper margi'n'a portions disposed" un- .der the. marg'i'na'i portions of'the top plate,

I lowerside plates having their-upper mar giinal porcions disposed: under the lowermarginal portions of the upper side plates, and abottom plate having its marginal port-ions disposed under the lower marginal portions ,65 of the lowerside plates, the top and side plates having a normal curvature equal to the minimum diameter of the form, and the bottom plate having a normal curvature equal to the maximum diameter ofthe form, in combination with a mechanism for expanding and contracting the form, said mechan sm including links connected with the middle portions of the top and bottom plates and upper marginal portions of the side plates.

A iorm o f 'the character described pomprising a top plate, upper side plates having their upper marginal portions disposed under the marginal portions of the top plate, lower side plates having their up-' per marginal portions disposed under the plateskgand a bottom plate having its marginal portions disposed under the lower marginal portions of the'lower side plates, the top andside plates having a normal cur- .va ture equal to the. minimum diameter of the form, and the bottom plate having a normal curvature equal to the maximum diameter of the form, and stiffening bars secured to the middle portions of the. top and bottom platesand upper marginal portions of the side plates, in combination with a mechanism for expanding and contracting the form, said mechanism including a plurality of radially-disposed links connected lower marginalfportions of the upper side with the said bars, and means for actuating the links.

11. In'a collapsible form, the combination of a plurality of overlapping slidable plates of different transverse dimensions and some of the plates having a normal curvature less than the maximum diameter of the form,

sets of oppositely-inclinedand crossed links connected 'with the plates, alined collars to which the sets are independently connected,

and an operatingqscrcw having right and left threads engaging the collars respectively.

12. In a collapsible form, the combination of a plurality of resilient arcuate lates arranged in overlapping relation an slidable 7 one on another, certain of the plates being tensionedto spring inwardly when the form is expanded, separate sets of links arranged within the form and reversely lIlClll'16d,'COX' responding links ,of both sets being disposed parallel with each other and connected with the same plate of the-form and also crossing each. other, a collar to which each set of links are connected, and a screw having right and left .threads'engaging the respective collars.

13. In a collapsible form, the combination I of a plurality of resilient arcuate plates arranged in ovelapping relation and siidable one on another to change in curvature'as the form expands and contracts, with a mechanism for expanding and contracting the form, said mechanism comprisingtwo sets of llIlkS reversely inclined to the axis of the form and corresponding links of both sets being parallel and disposed one across the other, pivotal connections between the outer ends of the links and plates, alined collars, pivotal connections between the links and collars, and a screw having right and left threads engaging the respective collars, there 7 being as many pairs of links as there are plates.

14. A collapsible form comprising an arcuate top plate, a pair of arcuate upper side plates of less width than the top plate and extending under the latter, opposite lower side plates of less width than the upper side plates and extendin underthe latter, a bottom arcuate plate 0? greater width than the combination with means for expanding and contracting the form, said means includ ng elements connected with the said members, and an actuator connectedwith the elements.

CHARLES a. BESSER. Witnesses: V

MERLE A. Bisssnn, C.'E. HAMPTON. 

